HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF MALONALDEHYDE USING P-NITROPHENYLHYDRAZINE AS A DERIVATIZING REAGENT

A high-performance liquid chromatographic procedure for the specific determination of free malonaldehyde (MA) is described. MA solution was mixed with 1 M acetate buffer (pH 3.76) and was reacted with p-nitrophenylhydrazine (NPH) hydrochloride solution in ethanol. An aliquot of the reaction mixture was injected into a C18-5 column with a mobile phase consisting of acetonitrile-isopropanol-0.01 M sodium dihydrogenphosphate (30:10:60, v/v/v) and detection at 315 nm. MA reacted readily with NPH in a weakly acidic medium at room temperature, giving 1-(p-nitrophenyl)pyrazole. The method is specific for free MA. The response was linear in the range 36-720 ng/ml of MA and the detection limit was 6 ng/ml with a 20-μl injection. © 1990.